<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>display</title>
    <style>
        /*值为 "block" 的 display 属性会导致两元素间的换行*/
        a {
            display: block;
        }
        /*隐藏*/
        a.a1{
            display: none;
        }
    </style>
</head>
<body>
<a  href="#" target="_blank">HTML</a>
<a href="#" target="_blank">CSS</a>
<a href="#" target="_blank">JavaScript</a>
<a class="a1" href="#" target="_blank">CSS</a>
</body>
</html>